Car safety seats for children are commercially available in a many configurations corresponding to differences in the age, weight, and size of the child being transported. Parents can choose a car seat that is not only the correct size, but also suits their tastes, budget, and life style. As children grow in size and maturity level, they need different kinds of car seats. For example, a child may initially use a rearwardly facing infant car seat, then graduate to a forward facing toddler seat with an integrated harness, and finally to a belt positioning booster seat utilizing the vehicle's lap and shoulder belt system before being able to safely use the vehicle's seat belts alone.
There are many car seats on the market that can be used in multiple configurations. For instance, a forward facing car seat with an integral harness appropriate for a 20-40 pound child might accommodate a child weighing 30-100 pounds as a belt positioning booster seat with the removal of the harness and utilizing the vehicle's lap and shoulder belts. This is convenient for the care giver because it means fewer seats to purchase. Some parents choose to buy a belt positioning booster seat for their older child. Such a booster seat may be configured with a high back, such as is disclosed in U.S. Pat. No. 6,682,143, granted to Davis Amirault on Jan. 27, 2004, or can have no back at all. Older children who don't want to be seen sitting in a “baby seat” like this option and parents don't have to manage a big bulky car seat.
Currently available car seats typically have a monolithic shell, i.e. the back and seat cannot be used separately. Some car seats are designed to have a no back base option, but are configured as a separate seat fastened under the monolithic seat and back, such as is disclosed in U.S. Pat. No. 4,754,999, issued on Jul. 5, 1998, to James Kain. The problem with this configuration is the redundancy of seats; one as part of the monolithic shell, and one as a seat only.
The basic purpose of a child's car seat is to protect the child in case the vehicle in which the car seat is mounted is involved in a crash event. Protecting the child involves limiting excursion and controlling the forces exerted on the child from the vehicle undergoing a crash event. Improper installation of a car seat is a major factor in a loss of protection for the child. If the car seat requires a complicated or complex belt path along which the vehicle seat belt is positioned to secure the car seat to the vehicle seat, the likelihood that the car seat will be properly installed is diminished. A belt path for the vehicle seat belt that is more visible and easier to access will increase the likelihood that the car seat will have a tight, proper installation.
During the first year of the life of a baby, the child should be positioned in a car seat in a manner to be facing rearwardly. When the child is over a year old, the child can be placed in the car seat in a manner that the child is facing forwardly. Presently known car seats require a remounting of the car seat and a repositioning of the vehicle seat belt to accomplish this conversion in orientation or the substitution of a different and larger car seat. Each time the car seat is reconfigured or moved from one vehicle to another, a new opportunity to improperly mount the car seat on the vehicle seat is presented, which can be aggravated by a non-intuitive, complicated belt path for mounting the car seat.
Many child car seats provide options for reclining the seat relative to the vehicle seat on which the car seat is mounted. Most known child car seats require a readjustment of the vehicle seat belt when changes are made to the recline orientation of the car seat. Readjusting the vehicle seat belt is an inconvenience to the person making the recline adjustment and provides an additional opportunity for the car seat to become improperly installed, which would not provide the optimum safety for the child positioned within the car seat. Some sources estimate that over 80% of car seats are incorrectly installed and proper car seat installation is essential for the car seat to protect the occupant.
In the rear facing mode, a baby must be oriented at a certain angle in order for the infant to breathe correctly while being positioned correctly in the event of a crash. If the car seat is too upright when in the rear facing mode, the baby's head can fall forward and occlude the child's airway. If the car seat is reclined too much, the infant can incur high loads on the neck and shoulders through the harness straps which prevent the baby from exiting the top of the car seat in the event of a collision. In the forward facing mode, a car seat that is too upright will cause a child to be uncomfortable on long trips, particularly when the child wants to sleep. A car seat that is mounted on a separate base and has the ability to change the angle of the car seat relative to the base must be able to stay locked at the selected angle in the event of a crash. Having the ability to recline the car seat easily to the correct position and lock the car seat in that selected position is necessary for the safety and comfort of the child.
It would also be desirable to provide a child car seat that has a recline mechanism that is cooperable with the separate base part to adjust the angle of the car seat relative to the base. Preferably, the recline mechanism would be intuitively operable, preferably by pulling up on the recline actuator handle to cause the recline mechanism to disengage and permit an adjustment of the recline angle. It would also be desirable to incorporate a level indicator to provide a positive feedback that the car seat has been correctly installed on the vehicle.